Marriage in modern times

It amuses me that gays want to marry when traditional marriages (man-woman marriages) are becoming increasingly unpopular. The institution of marriage might have been created so that children feel secure. The death do us apart motto has long been substituted with till divorce kicks in which meant financial burden and so marriage itself has been kicked off as a concept or happens with prenups. I wonder what makes gays want to marry. Perhaps it is because they do not have many quarreling couples as examples for a deterrent.